Laminated-lever switch.



PATENTED MAY 19, 1903. E. M. HEWLETT & c. c. BADEAU.

LAMINATED LEVER SWITCH.

APPLICATION FILED D30. 16, 1898.

N0 MODEL,

QM m l U 1 U 7 M MW s :2! 25% 3 t :I: z nm fi ma H b UNITED rammed May19, 1902.

EDWARD M. HEWLETT AND CHARLES C. BADEAU, OF SOHENEOT ADY, NEW

YORK, ASSIGNORS TO THE GENERAL ELECTRIC COMPANY, A CORPORA- TION OENEWYORK.

LAMINATED-LEVER SWITCH- QPECIFIGATION forming part of Letters Patent No.728,231 dated-May 19, 1903. Application filed Deoemherlii, 1898. SerialN05699A38. (No model.)

To all whont it may concern:

Be it known that we, EDWARD M. HEWLETT and CHARLES C. :BADEAU,citizensof the- United States,residing at Schenectady,county 5 ofSchenectady, in the State of New York,

have invented certain new and useful Improvements in Laminated-LeverSwitches, (Case No. 862,) of which the following is a specification.

Our present invention relates to switches for electric circuits,particularly to those intendedto carry largecurrents, and which aretherefore of considerable weight and size. In switches for this serviceit has heretofore been I 5 customary to make the stationary terminalswith some degree of flexibility, so that they would make a firm rubbingcontact withthe largeand heavy solid blade of the switch, If the fixedterminals are small enough to get' the required spring, they are 'notsufficiently heavy to carry the required current. 1 If made large, theyare too stiff. In our invention we provide for the switches fixedterminals of ample size for the designed current. These are rigid, orsubstantially so. .The switch-' blades, however, are laminated and makeside-bearing sliding or rubbing "contact with the fixed terminals. Inorder to avoid the difficulty of pivoting the laminated blades, weattach them to a rigid bar pivoted at one end to a fixed terminal of theswitch, the blades being attached near the middle, so that each end isfree. By this construction the blades and terminals may be as large and.5 thick as is desirable or necessary making.

good contact and carrying the rated .load

without undue heating. I

The drawings annexed show our invention as applied to a three-poleswitch, though of 0 course other kinds might be similarly made.

In the drawings, Figure 1 is afront elevation, and Fig. 2 a sideelevation, of the switch. In both the figures, A is the usual base orboard for the switch, of slate or other suit- 5 able insulatingmaterial.

B is the switch-handle, attached to a bar B, of insulating material,joining the three bars F F F, which carry the switch-blades. Adescription of one of these suffices for all, as the three are similar.

To .the bar F is affixed a cross-piece F.

-Upon each end of the cross-piece is a plate 1 00. --The blade maybecomposed of as many sheets of copper or, other conducting material'asmay be desired, and it is manifest 'thatincreasedcurrent-carryingcapacity may 'be 'obtained to almost any desired extent by simplyincreasing'the size of the switch.

A part of the outer en'd'of the bar F is formed on an arc struck fromthe center, on which the bar swings. Spring-terminals E E make or breakthe circuit as the switch is closed and opened upon contacts f, locatedon this p artof the .blade, these supplemental contacts being designedto break contact inopenin gtheswitch a little later thanthe. bridgecontacts, and thereby serving to take the arc and prevent injury to thebridging contacts. They may be shod, if desired, with carbon blocks,thus increasing their cheapness and durability and preventing spatteringof metal when the circuit is opened. In the illustrated construction thecenter terminal E is'made a little longer than the others, so that thisbladeofthe switch wilhmake contact before the other two. In theparticularswitch here shownit is so-arrangedin order to connect theequalizer (in a plant employing a number of compound-wound dynamos)before the positive and negative terminals of the generator areconnected to the bus-bars. One end of each terminal is threaded,-asshown'at'O I and the terminals are secured to the switchboard by nuts Cin the usual way.

By the construction here outlined we are enabled to make a switch whichwill carry large currents without undue heating and will always makegood contact between the it. l A,

blade and the fixed terminals. At the same time, if desired, only onekind of switch of this general type need be manufactured, changed onlyin size to adapt it to all ordinary requirements.

What we claim as new, and desire to secure by Letters Patent of theUnited States, is

1. Aswitch forheavy currents, having fixed terminals, a pivoted blade orbar entering and engaging thejaws of said terminals, and laminatedbridging contacts carried by said bar making rubbing side contact on theouter faces of the fixed terminals.

2. A switch fol-heavy currents, having fixed terminals, flexible bladesmaking side contact with the fixed terminals, a pivoted bar to which theblades are fixed, and supplementary terminals making and breakingcontact upon the bar.

3. The combination, in a switch, of a pair of slotted fixed terminals,2. bar pivoted in one of the slotted terminals and entering the slot inanother when the switch is closed, bridging contacts with free ends eachmaking rubbing side contact with a fixed terminal, and supplementaryterminals making and breaking circuit on the bar.

4. The combination, in a switch, of a pair of slotted fixed terminals, abar pivoted in one of the slotted terminals and entering the slot inanother when the switch is closed, a pair of flexible bridging contactsattached to the bar and having free ends, each of which

